1. Field of the Invention
This invention relates to angled bulldozer blades and, more particularly, to a slider plate assembly for positioning the thrust members of the blade adjusting mechanism.
2. Description of the Prior Art
Traditionally, bulldozer blades are angled in any one of several positions by means of thrust members carried by the blade being pivotally connected to any one pair of a plurality of bearings or brackets mounted on the side arms of a C-frame. To change the bulldozer blade adjustment from, for instance, an angle-right to an angle-left position, the thrust members are disconnected from the appropriate pair of bearings or brackets and are physically moved to the desired other pair of bearings or brackets whereupon they are reattached.
Some time ago, various forms of slide assemblies were provided for slidable attachment to rails mounted on the side arms of the C-frame. Hydraulic cylinders have been connected between the C-frame and the slider assemblies for moving the slider assembly relative to the C-frame for changing the bulldozer blade angle.
Under certain conditions and for certain types of operations, the infinitely adjustable angling of the bulldozer blade proved to be unsatisfactory in that the power means, such as the hydraulic cylinders, were subject to such continuous stresses as to create service problems. Additionally, the use of hydraulic cylinders to angle the blade adds considerable expense and complexity to the bulldozer assembly.
Still another method of adjusting the angle of the bulldozer blade was to provide several pre-positioned openings in the C-frame such that the slider assembly connected to the thrust members could be moved into alignment with the openings in the C-frame and a pin dropped therethrough to position the slider assembly and the bulldozer blade in the desired angled position. The use of the single pin made it difficult to readjust the blade angle since there was no easy way to remove the pressure created on the pin by the slider assembly and bulldozer blade. To remove the pin generally required considerable manipulation of the blade to provide a substantially thrust-free condition on the pin. Although the system provided for stops to position the slide for insertion of the pin, such stops did not remove the pressure on the pin for removing the pin.